The present invention relates in general to printing machines and, in particular, to an arrangement for reversing pressure of cylinders and/or rollers of a printing machine.
From DD Pat. No. 121,301 a device for reversing pressure of cylinders and rollers in a printing machine by means of a pneumatic or hydraulic motor is known.
However, the prior art devices of this kind possess the disadvantage that in the case when several sheets being printed run in the contact zone between a rubber (blanket) cylinder and a plate cylinder, or between the rubber cylinder and an impression cylinder, then printing pressure increases and, consequently a control pressure needed for stopping the printing has an extremely high value which normally cannot be delivered by a conventional hydraulic pressure control circuit designed for a normal operation of the printing machine.